Scripting: script.run reports .jsxbin scripts as unsupported (#176)

`effectcraft-cli script FILE` passes the file's text to script.run, which
ran a compiled .jsxbin script as JavaScript and failed with "SyntaxError:
unexpected '@'" at 1:1, while file.runScript already says .jsxbin isn't
supported.

script.run now refuses a script named `.jsxbin` or whose text starts with
the `@JSXBIN@` header, with file.runScript's message (one shared
constant). The check is in the command, so the CLI with or without
--bridge, MCP run_script and the Script Console all report it.

Tests: engine_entry_points (by header and by name), script_file_and_eval
(the CLI exits 1 with the message and no SyntaxError).

Co-Authored-By: Claude Opus 5.5 <[email protected]>

apps/effectcraft-cli/tests/cli.rs

@@ -239,4 +239,11 @@ fn script_file_and_eval() {
     let (code, v) = run_json(&["script", "--eval", "\nnope()"]);
     assert_eq!(code, 1);
     assert_eq!(v["error"]["line"], json!(2));
+    // A compiled .jsxbin script is reported as unsupported, not as a SyntaxError (#176).
+    let bin_script = tmp("compiled.jsxbin");
+    std::fs::write(&bin_script, "@JSXBIN@[email protected]@MyBbyBn0ABJAnAEjzFjBjMjFjSjUBfRBFeFjIjFjMjMjPff0DzACByB\n").unwrap();
+    let out = bin().args(["script", bin_script.to_str().unwrap()]).output().unwrap();
+    assert_eq!(out.status.code(), Some(1));
+    let err = String::from_utf8_lossy(&out.stderr);
+    assert!(err.contains(".jsxbin scripts are not supported: run the .jsx source") && !err.contains("SyntaxError"), "{err}");
 }